The Split Squat: A biomechanical breakdown and 3 Useful Variations

Split squats are one of the top exercises for not only strength training, but also athletic movement. Using unilateral movements allows for more rotation of the body, something many people benefit from. In this post, I want to go over what is actually happening in the body as you set up for a split squat, as well as what occurs as you descend into one. I also talk about 3 different variations of a split squat I have in my repertoire that can be used for different goals.

As you set up for a split squat, you are position one leg in front of the other. The front leg in the split squat is going to be biased towards an earlier propulsive position, while the back leg is going to be biased towards a later propulsive position. This is based on the gait cycle and the propulsive phases that correspond with each phase of gait.

Credit Physiopedia

The heelstrike phase coincides with an early propulsive phase, midstance coincides with a middle propulsive phase, and the toe off phase coincides with a late propulsive phase. The heel off phase is the point of maximum propulsion. You achieve maximum propulsion at the moment right before the heel breaks from the ground.

Gait and propulsion. CT = connective tissue

Essentially, when the leg is out in front of you, it is biased towards early propulsion; when it is under you, it is biased towards middle propulsion; when it is behind you, it is biased toward late propulsion. That said, in a split squat where your left leg is forward, you have a pelvis that is turned to your right, but turning to the left, since there is glute max activity on the backside leg pushing the pelvis in that direction. As you descend into your split squat, the front leg comes closer to a middle propulsive phase, since the hips are internally rotated when you are at 90 degrees of hip flexion. There is an increased demand for force, which will require increased internal rotation since that is a force-producing rotation. The back leg will be less internally rotated as you descend into the split squat, since most of the load will be placed on the front leg. This means less internal rotation required in the back leg relative to the front leg. Essentially, load is shifting as you descend and ascend in the split squat. This makes the exercise useful for influencing rotation of the body to a desired direction. If you are looking to influence somebody’s center of gravity by rotating their body to the right, you would perform a split squat with the right foot forward. If you’re looking to go left, you would put the left foot forward.

How might you be able to tell where to influence somebody’s center of gravity?

If you take a look at somebody’s bodyweight squat and they demonstrate a hip shift, the side they are shifting toward is the side they are rotated toward. If I shift into my right hip in a bodyweight squat, I am demonstrating a rotation to the right, which is where my center of gravity currently resides. The opposite is then true for a left hip shift. For a right hip shift, a left-foot-forward split squat becomes useful. The opposite would be true for a left hip shift - a right-foot-forward split squat is the tool here.

Split Squat Variations

With all of that said, there are some ways you can further manipulate a split squat in order to achieve your desired outcome. Here are some variations I love:

1) Ramp Split Squat

Placing a ramp or heel wedge under the front foot will result in more of a rotation toward the lead leg. This is because a ramp mimics what an early propulsive foot would look like, which will affect the overall rotation bias throughout the limb. The tibia will be behind the foot as it is in the early propulsive phase. This is known as a delay. You are delaying the forward translation of the tibia over the foot, which is useful for restoring a more supinated foot position since the foot does not have to pronate so quickly. Since we produce force into the ground via pronation, one can see how this would cause a delay in that pronation, and therefore influencing how quickly we are producing force into the ground.

2) Rear-foot-elevated Split Squat

Elevating the back foot will improve the body’s ability to internally rotate in the front leg, pushing them towards IR. It essentially is good for force production. This will push your center of gravity forward, more so than in a standard split squat. Pushing your center of gravity forward helps force production. A narrow ISA tends to benefit from this sort of movement since they have a limitation in force production and more concentric musculature on the front side of the body - this will act as an aid in reacquiring the force producing ability, while also eccentrically orienting musculature on the frontside of the body with the shift forward in the center of gravity. Regardless, this can still be used to promote more overall stiffness in the body.

3) Front-foot-elevated Split Squat

The front-foot-elevated split squat is similar to the ramp split squat in that it helps the body to yield better to forces. It shifts the body’s center of gravity backwards in space, which is a force-absorption strategy. This is because it delays how quickly the tibia will translate over the foot throughout the phases of propulsion. If we recall, a tibia that is behind the foot is in an early propulsive position. This mimics that to a degree. The difference in this vs. the ramp squat is that you get less of a rotation out of this move, but it is still useful for acquiring that delay strategy. A wide ISA will greatly benefit from this move, as they have a limitation in force absorption, as well as concentrically oriented musculature on the backside of the body. This tackles both of those limitations. Athletes greatly benefit from this move as it helps recapture some range of motion that is being sacrificed for the force production demands of their sport. To produce force, we concentrically orient the muscles on the backside of our body and create orientations throughout the body to produce high levels of force. Regardless of ISA, all athletes end up squeezing posteriorly (or creating an orientation in their body) for force production, so this helps manage that.

Give some of these variations a shot in your programming, or consider including them in programs for your clients or athletes based on their needs.